Laser drilling tool with articulated arm and reservoir characterization and mapping capabilities

Abstract

This application relates to systems and methods for stimulating hydrocarbon bearing formations using a downhole laser tool.

What is claimed is: 
     
       1. A laser perforation tool configured for use in a downhole environment of a wellbore within a rock formation, the tool comprising:
 perforation means configured for perforating the wellbore, the perforation means comprising one or more optical transmission media, the one or more optical transmission media being part of an optical path originating at a laser generating unit configured to generate a raw laser beam, the one or more optical transmission media configured for passing the raw laser beam; 
 a laser head coupled to the one or more optical transmission media and configured for receiving the raw laser beam, the laser head comprising an optical assembly for controlling at least one characteristic of an output laser beam; 
 a purging assembly disposed at least partially within or adjacent to the laser head and configured for delivering a purging fluid to an area proximate the output laser beam; 
 a plurality of orientation nozzles disposed about an outer circumference of the laser head, the plurality of orientation nozzles configured to control orientation of the laser perforation tool within the wellbore, the plurality of orientation nozzles being purge nozzles configured to provide thrust to the laser head to move the laser head within the wellbore and being movably coupled to the laser head to allow the orientation nozzles to rotate or pivot relative to the laser head to provide forward motion, reverse motion, rotational motion, or combinations thereof to the laser head relative to the wellbore; and 
 a control system to control the plurality of orientation nozzles thereby controlling at least one of a motion or a location of the laser head. 
 
     
     
       2. The tool of  claim 1 , where the optical assembly comprises:
 a splitter prism configured for receiving the raw laser beam and splitting the raw laser beam into one or more beams; and 
 a collimator disposed downstream of the prism and configured to receive the one or more beams and produce the output laser beam having a particular size or shape. 
 
     
     
       3. The tool of  claim 2 , where the optical assembly further comprises at least one additional lens disposed between the prism and collimator for delivering the output beam substantially perpendicular to or angled relative to a central axis of the laser head. 
     
     
       4. The tool of  claim 2 , where the collimator is configured to deliver the output laser beam substantially parallel to a central axis of the laser head. 
     
     
       5. The tool of  claim 2 , where the collimator is configured to deliver a diverging beam. 
     
     
       6. The tool of  claim 2 , where the collimator is configured to deliver a converging beam. 
     
     
       7. The tool of  claim 2 , where the collimator is configured to deliver a collimated beam. 
     
     
       8. The tool of  claim 1 , where the purging assembly comprises a plurality of purge nozzles disposed proximate the output laser beam and connected to a purge fluid supply, the purge nozzles configured to deliver a purge fluid to an area proximate the output laser beam. 
     
     
       9. The tool of  claim 8 , where at least a portion of the purge nozzles are vacuum nozzles connected to a vacuum source and configured to remove debris and gaseous fluids from the area proximate the output laser beam. 
     
     
       10. The tool of  claim 1 , where the tool comprises an articulated arm disposed between the laser head and the laser generating unit. 
     
     
       11. The tool of  claim 10 , where the articulated arm comprises a plurality of protective couplings disposed around the optical transmission media. 
     
     
       12. The tool of  claim 11 , where a flexible outer casing is disposed around the plurality of protective couplings. 
     
     
       13. The tool of  claim 10 , where the articulated arm comprises a snake robot having locomotion means for maneuvering the tool within the wellbore. 
     
     
       14. The tool of  claim 13 , where the locomotion means comprises at least one of an electrical motor or a hydraulic actuator. 
     
     
       15. The tool of  claim 1 , further comprising a centralizer coupled to the tool and configured to hold the tool in place relative to an outer casing in the wellbore. 
     
     
       16. The tool of  claim 15 , where the centralizer comprises a plurality of swellable packers. 
     
     
       17. The tool of  claim 1 , further comprising at least one acoustic camera coupled to the tool and configured to relay an image of an area proximate the laser head. 
     
     
       18. The tool of  claim 17 , where the at least one acoustic camera is disposed on the outer circumference of the laser head. 
     
     
       19. The tool of  claim 17 , where the at least one acoustic camera is also configured to characterize the formation. 
     
     
       20. A method of using a laser tool to stimulate a hydrocarbon-bearing formation, the method comprising the steps of:
 passing, through one or more optical transmission media, a raw laser beam generated by a laser generating unit at an origin of an optical path comprising the one or more optical transmission media; 
 positioning a laser tool within a wellbore within the formation via an articulated arm, the laser tool coupled to the laser generating unit; 
 orienting a laser head of the laser tool within the wellbore using a plurality of orientation nozzles disposed about an outer circumference of the laser head, the plurality of orientation nozzles configured to control orientation of the laser tool within the wellbore, the plurality of orientation nozzles being purge nozzles that are movably coupled to the laser head to allow the orientation nozzles to rotate or pivot relative to the laser head, the orienting comprising providing, by the purge nozzles, thrust to the laser head to move the laser head within the wellbore to provide forward motion, reverse motion, rotational motion, or combinations thereof to the laser head relative to the wellbore; 
 delivering the raw laser beam to an optical assembly disposed within the laser head; 
 manipulating the raw laser beam with the optical assembly to produce an output laser beam; and 
 delivering the output laser beam to the formation. 
 
     
     
       21. The method of  claim 20 , further comprising the step of imaging, using one or more acoustic cameras, an area proximate the laser head. 
     
     
       22. The method of  claim 20 , further comprising the step of characterizing the formation using the one or more acoustic cameras.